sys/doc/fs/pa

   1 .bp
   2 .SH
   3 Appendix:
   4 Maximum File Sizes in the 64-bit File Server
   5 .PP
   6 The maximum size of a single file in a Plan 9 file server's
   7 file system with 64-bit block numbers
   8 is determined by the file system block size
   9 (there are single, double, triple and quadruple indirect blocks).
  10 The maximum size is thus
  11 $d ( 6 + x + x sup 2 + x sup 3 + x sup 4 )$
  12 bytes, where
  13 $d = blocksize - ( 2 + 2 + 8 )$
  14 and
  15 $x = left floor d over 8 right floor$,
  16 8 being the size in bytes of a
  17 .I "long long"
  18 block number.
  19 .LP
  20 Note that
  21 $2 sup 63 ~ = ~ 9,223,372,036,854,775,808 ~ = ~ 8$
  22 EB (binary exabytes).
  23 .LP
  24 .KS
  25 .TS
  26 center ;
  27 c s s
  28 c c c
  29 n n n .
  30 Maximum File Sizes
  31 blocksize       max. file size  in bytes
  32 _
  33 1k      239.455G        257,112,525,120
  34 2k      7.73795T        8,507,967,771,456
  35 3k      59.4174T        65,330,091,351,360
  36 4k      251.779T        276,833,619,879,744
  37 5k      770.93T 847,646,649,807,168
  38 6k      1.87752P        2,113,900,586,253,120
  39 7k      4.0645P 4,576,215,491,839,296
  40 8k      7.93382P        8,932,685,435,522,880
  41 _
  42 9k      14.3102P        16,111,863,841,429,824
  43 10k     24.2524P        27,305,748,837,688,128
  44 11k     39.0823P        44,002,768,605,261,120
  45 12k     60.4146P        68,020,766,726,780,736
  46 13k     90.1856P        101,539,987,535,380,800
  47 14k     130.683P        147,136,061,463,530,304
  48 15k     184.575P        207,812,990,391,866,688
  49 16k     254.939P        287,036,132,998,029,120
  50 _
  51 17k     345.293P        388,765,190,105,491,776
  52 18k     459.621P        517,487,190,032,397,120
  53 19k     602.407P        678,249,473,940,389,184
  54 20k     778.66P 876,692,681,183,446,848
  55 21k     993.946P        1,119,083,734,656,717,120
  56 22k     1.22502E        1,412,348,826,145,348,416
  57 23k     1.53012E        1,764,106,401,673,323,840
  58 24k     1.89319E        2,182,700,146,852,294,464
  59 25k     2.32213E        2,677,231,972,230,412,608
  60 26k     2.82551E        3,257,594,998,641,165,120
  61 27k     3.41264E        3,934,506,542,552,206,656
  62 28k     4.09355E        4,719,541,101,414,192,960
  63 29k     4.87905E        5,625,163,339,009,614,144
  64 30k     5.78076E        6,664,761,070,801,627,968
  65 31k     6.81111E        7,852,678,249,282,893,120
  66 32k     7.98341E        9,204,247,949,324,402,496
  67 _
  68 33k     9.31184E        10,735,825,353,524,316,480
  69 \&...
  70 48k     60.666E 69,943,138,363,646,533,440
  71 \&...
  72 56k     131.149E        151,204,569,706,075,533,120
  73 \&...
  74 64k     255.734E        294,841,790,119,418,167,104
  75 .TE
  76 .KE